Fluid signal addressing system



Nov. 12, 1968 D. H. THORBURN FLUID SIGNAL ADDRESSING SYSTEM r 1 3% m m y b w 9m XQQN m 5m Qw N H wmw F mmw MN f m GM. b \W\4\\ W N 1% hm hm Filed April 12, 1967 Nov. 12, 1968 D. H. THORBURN FLUID SIGNAL ADDRESSING SYSTEM 4 Sheets-Sheet 2 Filed April 12. 1967 Z7zz/emf07'.

4 Sheets-Sheet 3 D. H THORBURN FLUID SIGNAL ADDRESSING SYSTEM Nov. 12, 1968" Filed April 12. 1967 United States Patent 3,410,501 FLUID SIGNAL ADDRESSING SYSTEM David H. Thorhurn, Oak Park, Ill., assignor to The Power Regulator Company, Skokie, 111., a corporation of Illinois Filed Apr. 12, 1967, Ser. No. 630,448 Claims. (Cl. 2435) ABSTRACT OF THE DISCLOSURE A fluidic addressing system particularly suitable for use with multistation pneumatic conveyors. The station address is binary-coded at the sending station and decoded to a decimal address near the receiving stations, using monoand bistable fluid relays. As a result, only binary signals need be communicated for long distances. The decimal address signal operates a conveyor switch for the addressed receiving station. The system may also be used to switch between conveyor loops.

This invention relates to an addressing system which employs fluid relays for encoding and decoding addressing signals. The system is particularly useful in connection with pneumatic tube conveyors, but it has a much broader scope of application and can indeed be used in any transport system wherein it is possible to effect destination addressing by means of fluidic control. Accordingly, the invention will be described in the environmental context of a pneumatic conveyor system for convenience only.

A wide variety of addressing systems for pneumatic conveyors have been heretofore employed, some using electrical control and others using pneumatic or hydraulic circuitry. These prior systems have functioned well in numerous applications, but all have exhibited serious drawbacks under certain specific modes of utilization. The present invention is particularly suitable for use in those pneumatic conveyor systems where the pneumatic carrier sending station and the destination addressing apparatus are relatively remote from the conveyor loop and the carrier receiving stations associated therewith. In addition, the present invention is particularly desirable for use in those applications where the high reliability, long life, and other advantages of fluidic control circuitry are important factors.

In accordance with the present invention, there is provided an addressing system for selecting from among a plurality of carrier receiving stations disposed about a pneumatic conveyor loop. Each of the receiving stations has associated therewith a deflector mechanism which serves to divert the passage of a carrier from the conveyor loop to the receiving station. The deflector mechanisms are operated by fluid signals received from the addressing system. The addressing system itself comprises an encoding means which generates a binary fluid signal indicative of one of the receiving stations. (Although the signal fluid may be hydraulic or pneumatic, the fluidic circuitry will hereinafter be referred to, for convenience, as pneumatically operated, preferably with air.) The binary pneumatic signal is transmitted through suitable conduits to a decoding means which generates a corresponding decimal pneumatic signal for use in operating the deflector means associated with the selected receiving station. Accordingly, when an operator at the sending station desires to address a carrier to a particular receiving station, he actuates the encoding means with an address signal corresponding to the desired receiving station. The encoding means converts this address signal to a corresponding binary pneumatic signal, and the binary signal is reconverted to a decimal 3,410,501 Patented Nov. 12, 1968 signal in the decoding means through an array of suitable pneumatic relays. In this manner, only binary signals need be communicated between the encoding and decoding means. The system may also be used for diverting passage of a carrier from one loop to another in a multi-loop conveyor system. The pneumatic addressing system of the present invention requires no electrical or electronic circuitry or apparatus and is thus extremely rugged and reliable.

The present invention will be more fully understood by considering the following description, with illustrative reference to the drawings, in which:

FIGURE 1 is a schematic illustration of a pneumatic tube conveyor system embodying the present invention;

FIGURE 2 is a schematic illustration of an exemplary embodiment of an encoding means which forms a part of the present invention;

FIGURE 3 is an idealized plan view of a bistable pneumatic relay for use in the present invention;

FIGURE 4 is an idealized plan view of a monostable pneumatic relay for use in the present invention;

FIGURE 5 is a schematic illustration of an exemplary embodiment of a decoding means which forms a part of the present invention;

FIGURE 6 is a sectional elevation of a portion of a conveyor tube with a conventional pneumatic carrier therein;

FIGURE 7 is an idealized plan view of a conventional deflector mechanism for use in the system of FIGURE 1; and

FIGURE 8 is a schematic illustration of a modification of a portion of the system of FIGURE 1.

Description of exemplary embodiment With specific reference to FIGURE 1, there is shown, schematically, a pneumatic tube conveyor system embodying the present invention. A main conveyor tube 38 is fed by a feeder tube 37 which communicates with a sending station 36. FIGURE 6 illustrates a portion of the feeder tube 37 with a conventional pneumatic carrier 37a in place therein. Disposed about the conveyor tube 38 in FIGURE 1 are receiving stations 190, 290, etc., through 990. Branch tubes 180, 280, etc., through 980, respectively connect the receivig stations 190 through 990 to the conveyor tube 38. Associated with each of the branch tubes 180 through 980, respectively, are deflector mechanisms positioned as indicated by the numerals 170, 270, etc., through 970. Associated with each of the deflector mechanisms 170 through 970, respectively, are operating mechanisms 160, 260, etc., through 960. The operating mechanisms through 960 operate the respective deflector mechanisms through 970 in response to pneumatic signals received in associated decimal signal conduits 150, 250, etc., through 950, respectively. The deflector mechanisms 170 through 970 and the operating mechanisms 160 through 960 may be of any suitable conventional type used in pneumatic conveyor systems, so long as the latter are adapted for pneumatic actuation.

FIGURE 7 schematically illustrates a conventional form of deflector mechanism 570 which includes an interior pivotal gate member 572 connected to an exterior link 574 by a spring-biased hinge member 576. The link 574 is pivotally attached, through another hinge 578, to the operating arm 562 of the operating mechanism 560. When no signal is present in the decimal signal conduit 550, the operating mechanism 560 is not actuated, and the biasing force on the hinge 576 causes the gate 572 to remain in the position shown, so that a carrier traveling in the main tube 38 will not be deflected into the branch tube 580. However, when a signal appears in the conduit 550, the operating mechanism 560 is actuated, causing movement of the arm 562 and consequent dis- 3 placement of the gate 572, so that a carrier traveling in the main tube 38 will be deflected into the branch tube 580.

The decimal signal conduits 150 through 950 communicate with a decoding device 39, which will be described in more detail hereinafter. The coding device 39 receives pneumatic signals through binary signal conduits 15, 25, 45 and 85, which communicate with an encoding device 35, which will likewise be described in more detail hereinafter. Although for convenience, the sending station 36 and the encoding device 35 are shown relatively near to the conveyor tube 38 and decoding device 39, they will normally be quite remote therefrom.

The operation of the system shown in FIGURE 1 may be broadly described as follows: It will be noted that the encoding device 35 includes a keyboard with switch keys numbered 1 through 9. It should be understood that keying of, for example, the switch key numbered 5 will result in addressing a carrier for ultimate destination at receiving station 590. Similarly, key 1 addresses for destination at receiving station 190, key 2 for destination at receiving station 290, etc. Assuming that an operator desires to send a carrier from the sending station 36 to the receiving station 790, he will key the number 7 switch on the encoding device 35. This will result in an appropriate binary pneumatic signal, which is representative of the decimal integer seven, being communicated through one of more of the binary signal conduits 15, 25, 45 and 85 (in this particular example, as will become apparent below, pneumatic signals will appear in conduits 15, and 45) to the decoding device 39. In response to the incoming binary signal from the encoding device 35, the decoding device 39 will generate a pneumatic signal in the conduit 750. The signal appearing in the conduit 750 will cause the operating mechanism 760 to open the deilector mechanism 770, thus opening a path through which a carrier in the conveyor loop 38 may leave the loop and pass through the branch tube 780 to the receiving station 790.

In like manner, the operator may address a carrier for ultimate destination at any one of the receiving stations 190 through 990. Because all of the deflector mechanisms 170 through 970 will remain closed except the one associated with the addressed receiving station, a carrier entering the conveyor loop 38 from the sending station 36 through the feed tube 37 will pass all receiving stations except the one to which it is addressed.

It should be apparent that the system shown in FIG- URE 1 could be modified in numerous ways, as for example, by the addition or subtraction of any desired number of receiving stations. In addition, the system could be expanded to include more than one' conveyor loop. For example, as shown in FIGURE 8, the deflector mechanism 570 could be employed to shunt a carrier to a second conveyor loop 38a which might include additional receiving stations. As another example, the system could include a plurality of sending stations, some or all of which might have associated therewith an addressing system. The system actually depicted in FIGURE 1 should be understood to be exemplary only.

Turning now to FIGURE 2, there is shown a schematic diagram of an exemplary encoding device which might be employed to advantage in the system shown in FIG- URE 1. The encoding device 35 includes an air supply line 55 with a branch supply line 56. Connected to the branch supply line 56 through conduits 11, 21, etc., through 91, are keyed switches 1, 2, etc., through 9. As contemplated in the present embodiment, the switches 1 through 9 are preferably simple air valves of the type which is momentary contact and normally off. Thus, depressing the key on the switch 7, for example, will allow air to pass from the conduit 71 through the switch 7 and into associated conduits 72, 73 and 74. When pressure on the key of the switch 7 is released, the air supply to the conduits 72, 73 and 74 will be terminated.

Also communicating with the air supply line 55 are bistable pneumatic relays 10, 20, 40 and 80. FIGURE 3 illustrates a typical bistable relay 10 suitable for use in the present invention. As shown therein, a power air stream enters through a conduit 13 and passes through an input duct 10a to a control chamber 10f. The power air stream may then pass through either output duct 10b or output duct 10c and exit respectively through conduit 16 or 15. Communicating with the control chamber 10 are control ducts 10d and 102 which are connected respectively to conduits 12 and 14. Due to the well known Coanda eifect, a power air stream leaving the relay 10 through the output duct 10b will continue to do so until a control impulse or jet is received through the control duct 10d, at which point the power air stream will be switched to the output duct 100. In like manner, the power air stream will continue thereafter to exit through the output duct 100 until a similar control signal is received in the control duct 10c, at which point the power stream will be switched back to exit from the duct 10b.

Referring again to FIGURE 2, the bistable pneumatic relays 10, 20, 40 and are connected to the air supply line 55 through power conduits 13, 23, 43 and 83 respectively, which communicate with the input ducts of the relays. One of the output ducts of each of the relays 10, 20, 40 and 80 is vented to atmosphere as indicated by the arrows 16, 26, 46 and 86, respectively. The other output duct of each of the bistable relays 10, 20, 40 and 80 is connected to the binary signal ducts 15, 25, 45 and respectively, which in turn communicate with the decoding device 39, as described above in connection with FIG- URE 1. One of the control ducts of the bistable relay 10 is connected to the switch 1 through a conduit 12. The conduit 12 also communicates with the switches 3, 5, 7 and 9 through conduits 33, 53, 73 and 93, respectively. In like manner, one of the control ducts of the bistable relay 20 is connected to the switch 2 through a conduit 22, one of the control ducts of the bistable relay 40 is connected to the switch 4 through a conduit 42, and one of the control ducts of the bistable relay 80 is connected to the switch 8 through a conduit 82. Again, as in the case of the conduit 12, the conduit 22 also communicates with the switches 3, 6 and 7 through conduits 32, 63 and 74 respectively. Similarly, the conduit 42 also communicates with the switches 5, 6 and 7 through conduits 52, 62 and 72 respectively, while the conduit 82 communicates with the switch 9 through conduit 92.

The remaining control ducts for each of the bistable relays 10, 20, 40 and 80 are connected with a. reset line 58 through conduits 14, 24, 44 and 84, respectively. The reset line 58 is connected to a reset switch 57, which is in turn connected to the branch supply line 56.

The operation of the encoding device 35 may now be described. Assume, for example, that the operator wishes to address a pneumatic carrier to the receiving station 790 as shown in FIGURE 1. He will accordingly depress the key on the switch 7. This will cause air from the branch supply line 56 to be communicated through the conduit 71 to the conduits 72, 73 and 74. The air in the conduits 72, 73 and 74 will in turn be communicated to the left-hand control ducts of the bistable relays 10, 20 and 40 through the conduits 12, 22 and 42, respectively. Assuming that the initial state of the relays 10, 20 and 40 was such that the air entering respectively through the conduits 13, 23 and 43 was vented to atmosphere through the vents 16, 26 and 46 respectively, the relays will 'be switched to their alternate state. Thus, depression of the key on the switch 7 will cause a pneumatic signal to be generated in the binary signal conduit 15, '25 and 45. Because the relays 10, 20 and 40 are bistable, the signals in the conduits 15, 25 and 45 will persist until the reset switch 57 is actuated.

The reset switch 57 is preferably a simple momentary contact, normally off air valve similar to that used for the keyed switches 1 through 9. When the reset switch 57 is actuated, air from the branch supply line 56 will pass through the reset line 58 and thence the conduits 14, 24 and 44. Since as described above, the conduits 14, 24 and 44 communicate with the right-hand control ducts of the relays 10, and 40 respectively, the relays will be switched or reset to their initial state, so that the power air stream will be vented to atmosphere through the vents 16, 26 and 46 respectively. At this point, there will no longer be pneumatic signals in the binary signal conduits 15, and 45.

It should be understood that the bistable pneumatic relays 10, 20, and 80 represent the binary digits necessary to provide the binary equivalents of the decimal integers one through nine associated with the switches 1 through 9. Under the well-known binary progression where n is the number of binary digits (or, in the present case, the number of bistable relays) available, the number of decimal integers which can be accommodated is represented by the sum Thus, in the present case, the four bistable relays 10, 20, 40 and 80 could accommodate switches for fifteen receiving stations, although for simplicity only nine have been shown. Similarly, with the addition of another bistable relay, a total of thirty-one receiving stations could be handled, etc.

It is important to note that, although in the present exemplary embodiment there are nine (and potentially fifteen) receiving stations to which a carrier may be addressed, only the four binary signal conduits 15, 25, and 85 are required to transmit the binary addressing signal from the encoding device 35 to the decoding device 39. In large conveyor systems, and in other systems where fiuidic addressing might be employed, this feature would result in a great saving in cost and material. If the pneumatic addressing were done on a decimal basis only, it would be necessary to provide a signal conduit for each receiving station. Under the system of the present invention, however, because the transmitted signals are expressed in binary form, the number of signal conduits required is greatly decreased. Of course, as is clear from the above mathematical expressions, this decrease becomes proportionately much more significant as the number of receiving stations or conveyor loops is increased.

Of course, it must be recognized that the embodiment described in FIGURE 2 is merely exemplary, and numerous modifications may be made to suit particular applications. For example, as indicated above, the number of receiving stations, and correspondingly, the number of switches and bistable pneumatic relays, could be expanded to any degree desired. Also, although only a single loop conveyor is illustrated in FIGURE 1, a system might include numerous loops and accordingly certain switches in the encoding device 35 could be used for diverting carrier passage between loops. Moreover, if desired, the bistable relays could be dispensed with entirely. Their function in the illustrated embodiment is to provide an amplification stage, as well as a convenient means for resetting the system between carrier addressing and transport operations. If the bistable relays were eliminated, it would be desirable to provide a suitable type of locking contact switch to replace the momentary contact switches 1 through 9. In such circumstances, the system would be reset simply by unlocking the switch. Furthermore, although the reset switch 57 as shown is adapted to be actuated manually, the same switch could be adapted for automatic actuation by the diversion of a carrier from the conveyor loop 38 to one of the receiving stations. In addition, further amplification stages could be provided by adding bistable relays to the system in cascade.

Turning now to FIGURE 5, there is shown a schematic diagram of an exemplary embodiment of a decoding device 39 which is suitable for use in the system illustrated in FIGURE 1. Included in the decoding device 39 are bistable pneumatic relays 100, 200, 400 and 800 which are similar in all respects to the relays 10, 20, 40 and described in connection with FIGURES 2 and 3. The left-hand control ducts of the bistable relays 100, 200, 400 and 800 are connected respectively to the binary signal conduits 15, 25, 45 and leading from the encoding device 35. The right-hand control ducts of the bistable relays 100, 200, 400 and 800 are connected respectively to a reset conduit 68 by conduits 104, 204, 404 and 804. The reset conduit 68 is connected to a reset switch 66 which is in turn connected to an air supply line 65 through a conduit 67. The reset switch 66 operates in a fashion similar to the switch 57 described above in con ncction with FIGURE 2.

The input ducts of the bistable relays 100, 200, 400 and 800 are respectively connected to the air supply line 65 through conduits 102, 202, 402 and 802,, and the lefthand output ducts 101, 201, 401 and 801, respectively, are vented to atmosphere. In like manner, the right-hand output ducts of the relays 100, 200, 400 and 800 communicate with conduits 111, 211, 411 and 811. The bistable relays 100, 200, 400 and 800 operate in a similar manner to the relays 10, 20, 40 and 80 described above with reference to FIGURE 2. Thus, assuming for example that a pneumatic signal is received in the binary signal conduit 15, and assuming that the initial state of the relay was such that the incoming power air stream through conduit 102 was exhausted to atmosphere through vent 101, the incoming signal in the conduit 15 will switch the relay 100 so that the power air stream will exit through conduit 11. Actuation of the reset switch 66 will cause switching of the power air stream back to the atmospheric vent 101.

As was true in connection with the encoding device of FIGURE 2, the bistable relays 100, 200, 400 and 800 in the decoding device 39 provide amplification and a convenient means for resetting the system. Here, too, the reset switch 66 could be automatically actuated by diversion of a carrier from the conveyor loop 38 to the addressed receiving station. Again, the bistable relays could be dispensed with entirely, in which case the binary signal conduits 15, 25, 45 and 85 would communicate directly with the conduits 111, 211, 411 and 811 respectively.

The decoding device 39 also includes a number of monostable pneumatic relays such as the one designated by the numeral 110. FIGURE 4 illustrates a typical monostable pneumatic relay suitable for use in the present invention. The monostable relay includes an input duct 110a communicating with the conduit 111 and leading to a signal chamber 110 Output ducts 11% and 1100, which are connected respectively to conduits 121 and 112, communicate with the control chamber 110 A control duct 110d, which is connected to conduit 301 also communicates with the control chamber 110 as does a vent 110e. A power air stream entering through the conduit 111 passes through the input duct 110a and into the chamber 110f. The relay 110 is constructed so that the power air stream will normally leave the relay through the output duct 11% and the conduit 121, due either to Coanda effect or alignment of the ducts 110a and 110b, depending upon the type of relay construction chosen. However, when a control jet is received in the control duct 110d through the conduit 301, the power air stream will be diverted so as to exit through the output duct 110a and the conduit 112. Due to the construction of the relay 110, this state will persist only so long as the control jet persists in the control duct 110d. When the control jet is terminated, the power air stream will resume its original path and exit through the output duct 11011 and the conduit 121.

The monostable relays depicted in FIGURE 5 are shown schematically, and are designated by three-digit reference numerals ending in zero. It will be noted that one of the two output ducts for each of the monostable relays is indicated schematically by a broken line, and one by a solid line. The solid line indicates the stable position of the relay. Accordingly, in the relay 110 for example, a pneumatic signal entering the relay through the conduit 111 will normally leave the relay through the conduit 121. It is only when a pneumatic signal is received in the conduit 301 that the incoming power air stream will be exhausted to atmosphere through vent 112. Similarly, in the case of the monostable relay 310, the incoming air stream through the conduit 311 is normally exhausted to atmosphere through the vent 312, and it is only when a signal appears in the conduit 103 that the air stream will be diverted to exit through the conduit 321.

It is unnecessary to describe in detail each of the monostable relays and its interconnection with the other monostable and bistable relays. An example of the operation of the decoding device 39 should sutfice to make clear the functional nature of the interconnection. It should be understood that the ultimate result of the array of monostable and bistable relays is to generate, in response to an incoming binary pneumatic signal in the binary signal conduits 15, 25, 45 and 85, a corresponding decimal pneumatic signal which will appear in that one of the decimal signal conduits 150 through 950 which is associated with the addressed receiving station.

Assume, for example, that the operator has depressed the key of switch 1 in the encoding device 35 as illustrated in FIGURE 2. In accordance with the operation of the encoding device 35, a binary signal corresponding to the decimal integer one will be received at the decoding device 39. In this instance, this will be a pneumatic signal appearing in the binary signal conduit 15. The signal in the conduit will cause the bistable relay 100 to switch from its initial vented state to its alternate state in which the incoming power air stream in the conduit 102 will be diverted to exit through the conduit 111. It will be noted that the conduit 111 has three monostable relays 110, 120 and 130 which are interconnected in cascade fashion and which terminate in the decimal signal conduit 150. Since, as described above, the normal state of the monostable relays 110, 120 and 130 is as indicated by the solid lines, and since no signals appear in the conduits 301, 501 and 901, a pneumatic signal will appear in the decimal signal conduit 150. Thus, as illustrated in FIGURE 1, the operating mechanism 160 will operate the deflector mechanism 170 to divert the addressed carrier from the conveyor loop 38 to the receiving station 190.

As another example, assume that the operator wishes to address a carrier to receiving station 790, and accordingly depresses the switch 7. Pneumatic signals will appear in the binary signal conduits 15, 25, and 45 and will accordingly switch the bistable relays 100, 200 and 400 so that pneumatic signals appear in the respective conduits 111, 211 and 411. Under such conditions, pneumatic signals will also be communicated through the conduits 109 and 107 to the monostable relay 710, through the conduit 207 to the monostable relay 720 and through the conduit 407 to the monostable relay 730. It should be noted, however, that the monostable relays 710, 720 and 730 are arranged in cascade, the former being connected to the air supply line 65 through a conduit 711, and the later terminating in the decimal signal conduit 750. Accordingly, the signals received in the conduits 107, 207 and 407 respectively cause switching of the monostable relays 710, 720 and 730 and thus result in a pneumatic signal being produced in the decimal signal conduit 750.

However, because of the arrangement and interconnection of the bistable and monostable relays, signals would also be produced in the decimal signal conduits 150, 250, 350, 450, 550 and 650. To avoid this result, monostable relays 330, 530 and 630 are connected to the decimal signal conduits 350, 550 and 650 respectively, and are adapted to be switched when a signal is present in the decimal signal conduit 750. To this end, conduit 750 communicates with the control ducts of the monostable relays 330, 530 and 630 through conduits 703, 705 and 706 respectively. Thus, when a signal is present in the decimal signal conduit 750, no signal can be present in the decimal signal conduits 350, 550 and 650. In like manner, monostable relays 110, 120, 210, 220, 410 and 420 are provided to insure that no signals will appear in the decimal signal conduits 150, 250 and 450 when signals appear in the conduits 331, 531 and 631 respectively.

It would be well within the skill of one familiar with the art to trace through additional examples and, indeed, to establish expanded arrays and interconnections of monostable and bistable relays whereby additional receiving stations and/or conveyor loops could be added to the system. The basic criterion in establishing fluidic circuitry for the decoding device 39 is that a binary addressing signal received therein will result in the generation of a pneumatic signal in that one of the decimal signal conduits which communicates with the operating mechanism of the addressed receiving station or conveyor loop, and only in that decimal signal conduit.

I claim:

1. A fluidic addressing system for selecting from a plurality of destinations along a main flow route, wherein each of said destinations has associated therewith transfer means for diverting flow from said main route to said destination, said system comprising: encoding means responsive to an external signal indicative of one of said destinations for generating a binary fluid signal which is likewise indicative of said one of said destinations; decoding means responsive to said binary fluid sig- 11211 for generating a corresponding decimal fluid signal; and means responsive to said decimal fluid signal for operating that one of said transfer means which is associated with said one of said destinations.

2. In a pneumatic conveyor system having at least one carrier sending station; at least one conveyor loop; a plurality of carrier receiving stations positioned along said loop; and a plurality of deflector means, one associated with each of said receiving stations and operable in response to a pneumatic signal to divert a carrier from said loop to said receiving station; the combination thereof with a pneumatic addressing system comprising: encoding means, including binary generating means responsive to an external signal indicative of one of said receiving stations for generating a binary pneumatic signal which is likewise indicative of said one of said receiving stations; and decoding means, including decimal generating means responsive to said binary pneumatic signal for generating a corresponding decimal pneumatic signal, and means for applying said decimal pneumatic signal to that one of said deflector means which is associated with said one of said receiving stations.

3. The combination of claim 2, wherein said binary generating means comprises a plurality of pneumatic switches, one for each of said receiving stations and representative of a decimal integer indicative of that receiving station; and a plurality of signal conduits, one for each of the binary digits necessary to provide binary digital equivalents of said decimal integers; said switches and conduits being interconnected such that when one of said switches is actuated, pneumatic signals will appear in those of said conduits which represent the binary digital equivalent of the decimal integer represented by said one of said switches.

4. The combination of claim 3, wherein said binary generating means includes a plurality of bistable pneumatic relays, one associated with each of said signal con duits, each adapted to be actuated by a pneumatic signal in said conduit; and means for resetting said bistable relays.

5. The combination of claim 4, wherein said means for resetting said bistable relays is adapted to be actuated by the diversion of one of said carriers to one of said receiving stations.

6. The combination of claim 2, wherein said decimal generating means comprises a plurality of output signal conduits, one associated with each of said receiving stations and representative of a decimal integer indicative of that receiving station; a plurality of input signal conduits, one for each of the binary digits necessary to provide binary digital equivalents of said decimal integers; and a plurality of monostable penumatic relays; the number of said relays and the interconnection thereof with said input and output conduits being such that when pneumatic signals appear in those of said input conduits which represent the binary digital equivalent of the decimal integer indicative of one of said receiving stations, a pneumatic signal will appear in that one of said output conduits which is associated with said one of said receiving stations.

7. The combination of claim 6, wherein said decimal generating means includes a plurality of bistable pneumatic relays, one associated with each of said input signal conduits and adapted to provide a pneumatic signal thereto in response to an actuating signal received from said encoding means; and means for reseting said bistable relays.

8. The combination of claim 7, wherein said means for resetting said bistable relays is adapted to be actuated by the diversion of one of said carriers to one of said receiving stations.

9. A pneumatic conveyor system comprising at least one conveyor loop, a plurality of carrier receiving stations positioned along said loop, deflector means associated with each of said receiving station and operable in response to a fluid signal to divert a carrier from said loop to said receiving station, and a plurality of carrier sending stations, each of said sending stations having associated therewith a fluidic addressing system comprising: encoding means, including binary generating means responsive to an external signal indicative of one of said receiving stations for generating a binary fluid signal which is likewise indicative of said one of said receiving stations; and decoding means, including decimal generating means responsive to said binary fluid signal for generating a corresponding decimal fiuid signal, and means for applying said decimal fluid signal to that one of said deflector means which is associated with said one of said receiving stations.

10. A pneumatic conveyor system comprising at least one carrier sending station; a plurality of conveyor loops; a plurality of carrier receiving stations; a plurality of deflector means operable in response to a pneumatic signal to divert a carrier from one of said loops to another of said loops or from one of said loops to one of said receiving stations; binary generating means responsive to an external signal for generating a binary pneumatic signal indicative of one of said deflector means; decimal generating means responsive to said binary pneumatic signal for generating a corresponding decimal pneumatic signal; and means for applying said decimal pneumatic signal to said one of said deflector means.

References Cited UNITED STATES PATENTS 3,055,612 9/1962 Stout 243-16 3,082,974 3/1963 Halpern 24316 3,227,396 1/1966 Joy 24316 3,361,384 1/1968 Thorburn 243-16 EVON C. BLUNK, Primaly Examiner.

H. C. HORNSBY, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,410,501 November 12, 1968 David H. Thorburn It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading to the printed specification, lines 3 and 4, "The Power Regulator Company should read The Powers Regulator Company Signed and sealed this 14th day of April 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

